Condensate recovery from remote cooling units

ABSTRACT

A cooling system has a chiller to remove heat from a cooling liquid and a plurality of remote cooling units each comprises a heat exchanger coil, a fan blowing air through the heat exchanger coil, a drip pan receiving drip water condensing on the heat exchanger coil, a cooling conduit connected to the chiller outlet and the heat exchanger coil, a return conduit connected to the chiller inlet and the heat exchanger coil, and a suction conduit connected to receive water from a pan outlet of the drip pan. A liquid pump circulates the cooling liquid through the chiller and through each remote cooling unit, and a suction pump connected to an output end of each suction conduit draws drip water from each drip pan through each of the suction conduits and deposits the drip water into a collector.

This disclosure relates to the field of cooling equipment, and in particular cooling systems comprising a chilling apparatus connected to a plurality of remote cooling units.

BACKGROUND

A common cooling system is provided by a chiller which removes heat from a cooling liquid, which liquid is then circulated to one or more remotely located coolers where it passes through a heat exchanger coil and then returns to the chiller to be cooled again. A fan creates an air stream through the coil and the air passing through the cooled coil is cooled and cools the room or enclosure where the heat exchanger is located. Such systems can be installed permanently in a building or the like, or can be portable for temporary use.

Portable systems typically include a chiller unit to cool the liquid, a pump to pump the cooled liquid, and a plurality of remote cooler units connected by hoses. Depending on the situation, a portable chiller unit can be connected to several remote cooler units by hoses that are 200-300 feet long.

SUMMARY OF THE INVENTION

The present disclosure provides a portable cooling system that overcomes problems in the prior art.

As the air passes through the cold heat exchanger coil, drip water condenses out of the air onto the coil and drips into a pan. In permanent systems this drip water is simply funnelled to a drain, however in portable systems this drip water or condensate must be gathered in a drip pan or the like, and in many situations where there is no convenient drain the drip pans must periodically be emptied manually.

In a first embodiment the present disclosure provides a cooling system comprising a chiller operative to remove heat from a cooling liquid passing through the chiller from a chiller inlet to a chiller outlet. A plurality of remote cooling units each comprises a heat exchanger coil and a fan operative to blow air through the heat exchanger coil, a drip pan configured to receive drip water that condenses on an exterior of the heat exchanger coil, a cooling conduit adapted for connection to the chiller outlet and a coil inlet of the heat exchanger coil, a return conduit adapted for connection to the chiller inlet and a coil outlet of the heat exchanger coil, and a suction conduit connected at an input end thereof to receive water from a pan outlet of the drip pan. A liquid pump is operative to circulate the cooling liquid through the chiller and from the chiller outlet to each remote cooling unit and back to the chiller inlet, and a suction pump connected at a suction port of the suction assembly to an output end of each suction conduit and operative to draw drip water from each drip pan through each of the suction conduits and deposit the drip water into a collector.

In a second embodiment the present disclosure provides a method of providing cooling to a plurality of neighboring enclosures. The method comprises providing a chiller operative to remove heat from a cooling liquid passing through the chiller from a chiller inlet to a chiller outlet; providing a remote cooling unit in each enclosure, each remote cooling unit comprising a heat exchanger coil; circulating the cooling liquid through the chiller and from the chiller outlet through the heat exchanger coil of each remote cooling unit and back to the chiller inlet; in each remote cooling unit, collecting drip water that condenses on an exterior of each heat exchanger coil; connecting an input end of a suction conduit to receive drip water collected in each remote cooling unit; and providing a suction at an output end of the suction conduit and drawing drip water from each remote cooling unit into a collector.

The present disclosure provides a system and method for conveniently collecting drip water that drips from the heat exchanger coils of a plurality of remote cooling units and conveying the collected drip water from each remote cooling unit to a centrally located collector. The disclosed system and method removes the need, especially in portable systems, for periodic attendance to empty and dispose of the drip water that collects at each of the remote cooling units.

DESCRIPTION OF THE DRAWINGS

While the invention is claimed in the concluding portions hereof, preferred embodiments are provided in the accompanying detailed description which may be best understood in conjunction with the accompanying diagrams where like parts in each of the several diagrams are labeled with like numbers, and where:

FIG. 1 is a schematic top view of an embodiment of the system of the present disclosure installed in a plurality of neighboring enclosures;

FIG. 2 is a schematic top view of the embodiment of FIG. 1 showing a single remote cooling unit;

FIG. 3 is a schematic sectional side view of a float operated valve on each pan outlet operative open the pan outlet when the drip water level rises to a selected level while maintain the drip water level at all times above the pan outlet to prevent air from entering the pan outlet into the suction conduit.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

FIGS. 1-3 schematically illustrate an embodiment of a cooling system 1 of the present disclosure. The system comprises a chiller 3 operative to remove heat from a cooling liquid passing through the chiller from a chiller inlet 3A to a chiller outlet 3B. A plurality of remote cooling units 5 is provided for operative connection to the chiller 3 to cool locations remote from the chiller 3. For example in a portable system 1 of the present disclosure the chiller 1 can be mounted on a trailer 7 or like vehicle and moved to a location adjacent to a number of different neighboring enclosures 9, typically rooms, separate buildings or a combination of like enclosures where cooling is desired. The remote cooling units 5, as well as the required pumps described below, can be carried on the trailer as well and the remote cooling units can moved into position in the desired enclosures 9 and connected to the chiller 3 by a conduit assembly 11.

Each remote cooling unit 5 comprises a heat exchanger coil 13 and a fan 15 operative to blow air through the heat exchanger coil 13. A drip pan 17 under the heat exchanger coil 13 is configured to receive drip water 19 that condenses on an exterior of the heat exchanger coil 13 and forms drops 19A as seen in FIG. 3 that fall into the drip pan 17. The remote cooling units 5 can be configured with larger or smaller heat exchanger coils 13 to provide remote cooling units 5 suitable for varying cooling capacities.

Each conduit assembly 11 comprises a cooling conduit 21 adapted for connection to the chiller outlet 3B and a coil inlet 13A of the heat exchanger coil 13, a return conduit 23 adapted for connection to the chiller inlet 3A and a coil outlet 13B of the heat exchanger coil, and a suction conduit 25 connected at an input end 25A thereof to receive water from a pan outlet 27 of the drip pan 17.

A liquid pump 29 is operative to circulate cooling liquid LQ through the chiller 3 and from the chiller outlet 3B to each remote cooling unit 5 and back to the chiller inlet 3A. A suction pump 31 is connected at a suction port 31A of the suction pump to an output end 25B of each suction conduit 25. The suction pump 31 creates a suction at the suction port 31A that is operative to draw drip water 19 from each drip pan 17 through each of the suction conduits 25 and deposit the drip water 19 into a collector 33.

To form each conduit assembly 11, each cooling conduit 21 is first insulated to preserve the cool temperature of the cooling liquid LQ as it passes from the chiller to the remote cooling unit 5. The cooling conduit 21, the return conduit 23, and the suction conduit 25 are enclosed together in a conduit cover, such as by wrapping a fabric or the like around the conduits, so the conduit assembly 11 is a single lengthy and flexible component that is readily rolled up for transport and then unrolled for deployment. A number of conduit assemblies 11 can be provided with different lengths, or all can be the same length, which can be typically 250 or more feet long to provide a wide reach from the chiller 3 to the farthest remote cooling units 5.

The suction pump 31 is a self-priming suction type water pump that pumps drip water 19 from each drip pan 17 through the suction conduits 25 and deposits the drip water 19 into the collector 33. It is contemplated that a mist maker 35 can be provided that is operative to transform the drip water 19 in the collector 33 into a mist 37 directed to cool the chiller 3.

The suction pump 31 can be configured to operate constantly, with the pan outlet open so that any drip water 19 that gathers in the drip pans 17 is drawn out right away.

An alternate arrangement is schematically illustrated in FIG. 3 which shows a float operated valve 39 on the pan outlet 27 of the drip pan 17. A float 41 is connected to the valve 39 by an arm 43 and the valve 39, arm 43, and float 41 pivot about a pivot axis PA. When the level DWL of the drip water 19 in the drip pan 17 rises above the level shown in FIG. 3, the float moves upward and the valve moves as indicated by the arrow, slightly opening the valve and allowing drip water 19 to be sucked out through the pan outlet 27, which is operated continuously so there is always suction at the pan outlet 27.

It can be seen that a slight rise of the float 41 will cause a correspondingly slight opening of the valve 39, allowing some drip water to exit the drip pan causing the float 41 to move down closing the valve 39 again, and this cycle will repeat continuously. In high humidity conditions where the drip water 19 drips more quickly the drip water level DWL will rise more quickly but the float 41 will then rise higher causing the valve 39 to open farther, allowing more water to be sucked out.

Humidity levels in the enclosures will vary, and so then will the rate of deposition of drip water 19 in the drip pans 17. The illustrated float system will operate in a wide range of humidity conditions, and maintains the drip water level DWL above the pan outlet 27 at all times and so air is not drawn into the suction conduit 25 and drip water 19 remains in the suction conduit 25 to maintain the suction pump 31 primed.

In some situations, such as low humidity conditions, rather than have the pump 31 working at all times it may be preferred to have the suction pump 31 operate only when needed. A sensor 45 can be provided that senses when all pan outlets 27 are closed, such as by sensing that no water is being drawn into the collector 33, or by sensing that suction pressure has increased, indicating that nothing is flowing into any of the suction conduits 25. When the sensor 45 senses that all pan outlets are closed, the suction pump is turned off.

A timer 47 can be provided to turn the suction pump 31 intermittently, and if the sensor 45 still senses that all pan outlets 27 are closed, the suction pump will be turned off again, while if one or more pan outlets are open the suction pump 31 will operate until all pan outlets 17 are again closed.

The present disclosure further provides a method of providing cooling to a plurality of neighboring enclosures 9. The method comprises providing a chiller 3 operative to remove heat from a cooling liquid LQ passing through the chiller 3 from a chiller inlet 3A to a chiller outlet 3B; providing a remote cooling unit 5 in each enclosure 9, each remote cooling unit 5 comprising a heat exchanger coil 13; circulating the cooling liquid LQ through the chiller 3 and from the chiller outlet 3B through the heat exchanger coil 13 of each remote cooling unit 5 and back to the chiller inlet 3A; in each remote cooling unit 5, collecting drip water 19 that condenses on an exterior of each heat exchanger coil 13; connecting an input end 25A of a suction conduit 25 to receive drip water 19 collected in each remote cooling unit 5; providing a suction at an output end 25B of the suction conduit 25 and drawing drip water 19 from each remote cooling unit 5 into a collector 33.

The present disclosure provides a system and method for conveniently collecting drip water 19 that drips from the heat exchanger coils 13 of a plurality of remote cooling units 5 and conveying the collected drip water 19 from each remote cooling unit to a centrally located collector 33. This system and method does not require any attendance to empty and dispose of the drip water that collects at each of the remote cooling units 5 as is typically required in portable applications.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous changes and modifications will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all such suitable changes or modifications in structure or operation which may be resorted to are intended to fall within the scope of the claimed invention. 

What is claimed is:
 1. A cooling system comprising: a chiller operative to remove heat from a cooling liquid passing through the chiller from a chiller inlet to a chiller outlet; a plurality of remote cooling units, each remote cooling unit comprising: a heat exchanger coil and a fan operative to blow air through the heat exchanger coil; a drip pan configured to receive drip water that condenses on an exterior of the heat exchanger coil; a cooling conduit adapted for connection to the chiller outlet and a coil inlet of the heat exchanger coil; a return conduit adapted for connection to the chiller inlet and a coil outlet of the heat exchanger coil; and a suction conduit connected at an input end thereof to receive water from a pan outlet of the drip pan; a liquid pump operative to circulate the cooling liquid through the chiller and from the chiller outlet to each remote cooling unit and back to the chiller inlet; and a suction pump connected at a suction port of the suction assembly to an output end of each suction conduit and operative to draw drip water from each drip pan through each of the suction conduits and deposit the drip water into a collector.
 2. The system of claim 1 wherein each cooling conduit is insulated.
 3. The system of claim 1 wherein for each remote cooling unit, the cooling conduit, the return conduit, and the suction conduit are enclosed together in a conduit cover.
 4. The system of claim 3 wherein the conduit cover is wrapped around the cooling conduit, the return conduit, and the suction conduit.
 5. The system of claim 1 wherein each of the remote cooling units comprises a float operated valve on the corresponding drip pan, wherein the float operated valve is operative to open the pan outlet when a level of the drip water in the drip pan rises to a selected level that is above the pan outlet.
 6. The system of claim 5 wherein the float operated valve is operative to close the pan outlet before the level of the drip water falls to a level where the pan outlet is exposed to the atmosphere.
 7. The system of claim 5 wherein the suction pump operates at all times when at least one pan outlet is open, and comprising a sensor operative to turn off the suction pump when all pan outlets are closed.
 8. The system of claim 7 wherein the suction pump comprises a timer operative to periodically start the suction pump.
 9. The system of claim 1 comprising a trailer, and wherein the chiller and remote cooling units are placed on the trailer for transport to a desired location.
 10. The system of claim 1 comprising a mist maker operative to transform the drip water in the collector into a mist directed to cool the chiller.
 11. A method of providing cooling to a plurality of neighboring enclosures, the method comprising: providing a chiller operative to remove heat from a cooling liquid passing through the chiller from a chiller inlet to a chiller outlet; providing a remote cooling unit in each enclosure, each remote cooling unit comprising a heat exchanger coil; circulating the cooling liquid through the chiller and from the chiller outlet through the heat exchanger coil of each remote cooling unit and back to the chiller inlet; in each remote cooling unit, collecting drip water that condenses on an exterior of each heat exchanger coil; connecting an input end of a suction conduit to receive drip water collected in each remote cooling unit; and providing a suction at an output end of the suction conduit and drawing drip water from each remote cooling unit into a collector.
 12. The method of claim 11 comprising circulating the cooling liquid through the chiller and from the chiller outlet to the heat exchanger coil of each remote cooling unit by connecting a conduit assembly between the chiller and each remote cooling unit.
 13. The method of claim 12 wherein the conduit assembly comprises: a cooling conduit connected between the chiller outlet and a coil inlet of the heat exchanger coil; a return conduit connected between the chiller inlet and a coil outlet of the heat exchanger coil; a suction conduit connected at an input end thereof to receive drip water from the remote cooling unit; and a conduit cover enclosing the cooling conduit, the return conduit, and the suction conduit.
 14. The method of claim 13 comprising, in each remote cooling unit, collecting drip water in a drip pan and allowing drip water in the drip pan to rise to a selected level before connecting the input end of the corresponding suction conduit to the drip pan.
 15. The method of claim 14 wherein, in each remote cooling unit, a pan outlet of the drip pan is connected to the input end of the corresponding suction conduit through a float valve, and wherein the float valve is operative to open and connect the pan outlet to the input end of the corresponding suction conduit when a level of the drip water in the drip pan rises to a selected level that is above the pan outlet.
 16. The method of claim 15 comprising ceasing to provide a suction at the output end of the suction conduit when the float valve in each of the remote cooling units is closed.
 17. The method of claim 11 mounting the chiller and the remote cooling units on a vehicle and transporting the chiller and remote cooling units to a location adjacent to the neighboring enclosures. 